xref: /freebsd/usr.sbin/i2c/i2c.c (revision cbd30a72ca196976c1c700400ecd424baa1b9c16)
1 /*-
2  * Copyright (C) 2008-2009 Semihalf, Michal Hajduk and Bartlomiej Sieka
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <err.h>
31 #include <errno.h>
32 #include <sysexits.h>
33 #include <fcntl.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <stdarg.h>
38 #include <unistd.h>
39 #include <sys/ioctl.h>
40 
41 #include <dev/iicbus/iic.h>
42 
43 #define	I2C_DEV			"/dev/iic0"
44 #define	I2C_MODE_NOTSET		0
45 #define	I2C_MODE_NONE		1
46 #define	I2C_MODE_STOP_START	2
47 #define	I2C_MODE_REPEATED_START	3
48 
49 struct options {
50 	int	width;
51 	int	count;
52 	int	verbose;
53 	int	addr_set;
54 	int	binary;
55 	int	scan;
56 	int	skip;
57 	int	reset;
58 	int	mode;
59 	char	dir;
60 	uint32_t	addr;
61 	uint32_t	off;
62 };
63 
64 struct skip_range {
65 	int	start;
66 	int	end;
67 };
68 
69 __dead2 static void
70 usage(void)
71 {
72 
73 	fprintf(stderr, "usage: %s -a addr [-f device] [-d [r|w]] [-o offset] "
74 	    "[-w [0|8|16]] [-c count] [-m [ss|rs|no]] [-b] [-v]\n",
75 	    getprogname());
76 	fprintf(stderr, "       %s -s [-f device] [-n skip_addr] -v\n",
77 	    getprogname());
78 	fprintf(stderr, "       %s -r [-f device] -v\n", getprogname());
79 	exit(EX_USAGE);
80 }
81 
82 static struct skip_range
83 skip_get_range(char *skip_addr)
84 {
85 	struct skip_range addr_range;
86 	char *token;
87 
88 	addr_range.start = 0;
89 	addr_range.end = 0;
90 
91 	token = strsep(&skip_addr, "..");
92 	if (token) {
93 		addr_range.start = strtoul(token, 0, 16);
94 		token = strsep(&skip_addr, "..");
95 		if ((token != NULL) && !atoi(token)) {
96 			token = strsep(&skip_addr, "..");
97 			if (token)
98 				addr_range.end = strtoul(token, 0, 16);
99 		}
100 	}
101 
102 	return (addr_range);
103 }
104 
105 /* Parse the string to get hex 7 bits addresses */
106 static int
107 skip_get_tokens(char *skip_addr, int *sk_addr, int max_index)
108 {
109 	char *token;
110 	int i;
111 
112 	for (i = 0; i < max_index; i++) {
113 		token = strsep(&skip_addr, ":");
114 		if (token == NULL)
115 			break;
116 		sk_addr[i] = strtoul(token, 0, 16);
117 	}
118 	return (i);
119 }
120 
121 static int
122 scan_bus(struct iiccmd cmd, char *dev, int skip, char *skip_addr)
123 {
124 	struct skip_range addr_range = { 0, 0 };
125 	int *tokens, fd, error, i, index, j;
126 	int len = 0, do_skip = 0, no_range = 1;
127 
128 	fd = open(dev, O_RDWR);
129 	if (fd == -1) {
130 		fprintf(stderr, "Error opening I2C controller (%s) for "
131 		    "scanning: %s\n", dev, strerror(errno));
132 		return (EX_NOINPUT);
133 	}
134 
135 	if (skip) {
136 		len = strlen(skip_addr);
137 		if (strstr(skip_addr, "..") != NULL) {
138 			addr_range = skip_get_range(skip_addr);
139 			no_range = 0;
140 		} else {
141 			tokens = (int *)malloc((len / 2 + 1) * sizeof(int));
142 			if (tokens == NULL) {
143 				fprintf(stderr, "Error allocating tokens "
144 				    "buffer\n");
145 				error = -1;
146 				goto out;
147 			}
148 			index = skip_get_tokens(skip_addr, tokens,
149 			    len / 2 + 1);
150 		}
151 
152 		if (!no_range && (addr_range.start > addr_range.end)) {
153 			fprintf(stderr, "Skip address out of range\n");
154 			error = -1;
155 			goto out;
156 		}
157 	}
158 
159 	printf("Scanning I2C devices on %s: ", dev);
160 	for (i = 1; i < 127; i++) {
161 
162 		if (skip && ( addr_range.start < addr_range.end)) {
163 			if (i >= addr_range.start && i <= addr_range.end)
164 				continue;
165 
166 		} else if (skip && no_range)
167 			for (j = 0; j < index; j++) {
168 				if (tokens[j] == i) {
169 					do_skip = 1;
170 					break;
171 				}
172 			}
173 
174 		if (do_skip) {
175 			do_skip = 0;
176 			continue;
177 		}
178 
179 		cmd.slave = i << 1;
180 		cmd.last = 1;
181 		cmd.count = 0;
182 		error = ioctl(fd, I2CRSTCARD, &cmd);
183 		if (error)
184 			goto out;
185 
186 		cmd.slave = i << 1;
187 		cmd.last = 1;
188 		error = ioctl(fd, I2CSTART, &cmd);
189 		if (!error)
190 			printf("%x ", i);
191 		cmd.slave = i << 1;
192 		cmd.last = 1;
193 		error = ioctl(fd, I2CSTOP, &cmd);
194 	}
195 	printf("\n");
196 
197 	error = ioctl(fd, I2CRSTCARD, &cmd);
198 out:
199 	close(fd);
200 	if (skip && no_range)
201 		free(tokens);
202 
203 	if (error) {
204 		fprintf(stderr, "Error scanning I2C controller (%s): %s\n",
205 		    dev, strerror(errno));
206 		return (EX_NOINPUT);
207 	} else
208 		return (EX_OK);
209 }
210 
211 static int
212 reset_bus(struct iiccmd cmd, char *dev)
213 {
214 	int fd, error;
215 
216 	fd = open(dev, O_RDWR);
217 	if (fd == -1) {
218 		fprintf(stderr, "Error opening I2C controller (%s) for "
219 		    "resetting: %s\n", dev, strerror(errno));
220 		return (EX_NOINPUT);
221 	}
222 
223 	printf("Resetting I2C controller on %s: ", dev);
224 	error = ioctl(fd, I2CRSTCARD, &cmd);
225 	close (fd);
226 
227 	if (error) {
228 		printf("error: %s\n", strerror(errno));
229 		return (EX_IOERR);
230 	} else {
231 		printf("OK\n");
232 		return (EX_OK);
233 	}
234 }
235 
236 static char *
237 prepare_buf(int size, uint32_t off)
238 {
239 	char *buf;
240 
241 	buf = malloc(size);
242 	if (buf == NULL)
243 		return (buf);
244 
245 	if (size == 1)
246 		buf[0] = off & 0xff;
247 	else if (size == 2) {
248 		buf[0] = (off >> 8) & 0xff;
249 		buf[1] = off & 0xff;
250 	}
251 
252 	return (buf);
253 }
254 
255 static int
256 i2c_write(char *dev, struct options i2c_opt, char *i2c_buf)
257 {
258 	struct iiccmd cmd;
259 	int ch, i, error, fd, bufsize;
260 	char *err_msg, *buf;
261 
262 	/*
263 	 * Read data to be written to the chip from stdin
264 	 */
265 	if (i2c_opt.verbose && !i2c_opt.binary)
266 		fprintf(stderr, "Enter %u bytes of data: ", i2c_opt.count);
267 
268 	for (i = 0; i < i2c_opt.count; i++) {
269 		ch = getchar();
270 		if (ch == EOF) {
271 			free(i2c_buf);
272 			err(1, "not enough data, exiting\n");
273 		}
274 		i2c_buf[i] = ch;
275 	}
276 
277 	fd = open(dev, O_RDWR);
278 	if (fd == -1) {
279 		free(i2c_buf);
280 		err(1, "open failed");
281 	}
282 
283 	cmd.slave = i2c_opt.addr;
284 	error = ioctl(fd, I2CSTART, &cmd);
285 	if (error == -1) {
286 		err_msg = "ioctl: error sending start condition";
287 		goto err1;
288 	}
289 
290 	if (i2c_opt.width) {
291 		bufsize = i2c_opt.width / 8;
292 		buf = prepare_buf(bufsize, i2c_opt.off);
293 		if (buf == NULL) {
294 			err_msg = "error: offset malloc";
295 			goto err1;
296 		}
297 	} else {
298 		bufsize = 0;
299 		buf = NULL;
300 	}
301 
302 	switch(i2c_opt.mode) {
303 	case I2C_MODE_STOP_START:
304 		/*
305 		 * Write offset where the data will go
306 		 */
307 		if (i2c_opt.width) {
308 			cmd.count = bufsize;
309 			cmd.buf = buf;
310 			error = ioctl(fd, I2CWRITE, &cmd);
311 			free(buf);
312 			if (error == -1) {
313 				err_msg = "ioctl: error writing offset";
314 				goto err1;
315 			}
316 		}
317 
318 		error = ioctl(fd, I2CSTOP, &cmd);
319 		if (error == -1) {
320 			err_msg = "ioctl: error sending stop condition";
321 			goto err2;
322 		}
323 		cmd.slave = i2c_opt.addr;
324 		error = ioctl(fd, I2CSTART, &cmd);
325 		if (error == -1) {
326 			err_msg = "ioctl: error sending start condition";
327 			goto err1;
328 		}
329 
330 		/*
331 		 * Write the data
332 		 */
333 		cmd.count = i2c_opt.count;
334 		cmd.buf = i2c_buf;
335 		cmd.last = 0;
336 		error = ioctl(fd, I2CWRITE, &cmd);
337 		if (error == -1) {
338 			err_msg = "ioctl: error writing";
339 			goto err1;
340 		}
341 		break;
342 
343 	case I2C_MODE_REPEATED_START:
344 		/*
345 		 * Write offset where the data will go
346 		 */
347 		if (i2c_opt.width) {
348 			cmd.count = bufsize;
349 			cmd.buf = buf;
350 			error = ioctl(fd, I2CWRITE, &cmd);
351 			free(buf);
352 			if (error == -1) {
353 				err_msg = "ioctl: error writing offset";
354 				goto err1;
355 			}
356 		}
357 
358 		cmd.slave = i2c_opt.addr;
359 		error = ioctl(fd, I2CRPTSTART, &cmd);
360 		if (error == -1) {
361 			err_msg = "ioctl: error sending repeated start "
362 			    "condition";
363 			goto err1;
364 		}
365 
366 		/*
367 		 * Write the data
368 		 */
369 		cmd.count = i2c_opt.count;
370 		cmd.buf = i2c_buf;
371 		cmd.last = 0;
372 		error = ioctl(fd, I2CWRITE, &cmd);
373 		if (error == -1) {
374 			err_msg = "ioctl: error writing";
375 			goto err1;
376 		}
377 		break;
378 
379 	case I2C_MODE_NONE: /* fall through */
380 	default:
381 		buf = realloc(buf, bufsize + i2c_opt.count);
382 		if (buf == NULL) {
383 			err_msg = "error: data malloc";
384 			goto err1;
385 		}
386 
387 		memcpy(buf + bufsize, i2c_buf, i2c_opt.count);
388 		/*
389 		 * Write offset and data
390 		 */
391 		cmd.count = bufsize + i2c_opt.count;
392 		cmd.buf = buf;
393 		cmd.last = 0;
394 		error = ioctl(fd, I2CWRITE, &cmd);
395 		free(buf);
396 		if (error == -1) {
397 			err_msg = "ioctl: error writing";
398 			goto err1;
399 		}
400 		break;
401 	}
402 	cmd.slave = i2c_opt.addr;
403 	error = ioctl(fd, I2CSTOP, &cmd);
404 	if (error == -1) {
405 		err_msg = "ioctl: error sending stop condition";
406 		goto err2;
407 	}
408 
409 	close(fd);
410 	return (0);
411 
412 err1:
413 	cmd.slave = i2c_opt.addr;
414 	error = ioctl(fd, I2CSTOP, &cmd);
415 	if (error == -1)
416 		fprintf(stderr, "error sending stop condition\n");
417 err2:
418 	if (err_msg)
419 		fprintf(stderr, "%s\n", err_msg);
420 
421 	close(fd);
422 	return (1);
423 }
424 
425 static int
426 i2c_read(char *dev, struct options i2c_opt, char *i2c_buf)
427 {
428 	struct iiccmd cmd;
429 	int i, fd, error, bufsize;
430 	char *err_msg, data = 0, *buf;
431 
432 	fd = open(dev, O_RDWR);
433 	if (fd == -1)
434 		err(1, "open failed");
435 
436 	bzero(&cmd, sizeof(cmd));
437 
438 	if (i2c_opt.width) {
439 		cmd.slave = i2c_opt.addr;
440 		cmd.count = 1;
441 		cmd.last = 0;
442 		cmd.buf = &data;
443 		error = ioctl(fd, I2CSTART, &cmd);
444 		if (error == -1) {
445 			err_msg = "ioctl: error sending start condition";
446 			goto err1;
447 		}
448 		bufsize = i2c_opt.width / 8;
449 		buf = prepare_buf(bufsize, i2c_opt.off);
450 		if (buf == NULL) {
451 			err_msg = "error: offset malloc";
452 			goto err1;
453 		}
454 
455 		cmd.count = bufsize;
456 		cmd.buf = buf;
457 		cmd.last = 0;
458 		error = ioctl(fd, I2CWRITE, &cmd);
459 		free(buf);
460 		if (error == -1) {
461 			err_msg = "ioctl: error writing offset";
462 			goto err1;
463 		}
464 
465 		if (i2c_opt.mode == I2C_MODE_STOP_START) {
466 			cmd.slave = i2c_opt.addr;
467 			error = ioctl(fd, I2CSTOP, &cmd);
468 			if (error == -1) {
469 				err_msg = "error sending stop condition";
470 				goto err2;
471 			}
472 		}
473 	}
474 	cmd.slave = i2c_opt.addr;
475 	cmd.count = 1;
476 	cmd.last = 0;
477 	cmd.buf = &data;
478 	if (i2c_opt.mode == I2C_MODE_STOP_START) {
479 		error = ioctl(fd, I2CSTART, &cmd);
480 		if (error == -1) {
481 			err_msg = "ioctl: error sending start condition";
482 			goto err1;
483 		}
484 	} else if (i2c_opt.mode == I2C_MODE_REPEATED_START) {
485 		error = ioctl(fd, I2CRPTSTART, &cmd);
486 		if (error == -1) {
487 			err_msg = "ioctl: error sending repeated start "
488 			    "condition";
489 			goto err1;
490 		}
491 	}
492 	error = ioctl(fd, I2CSTOP, &cmd);
493 	if (error == -1) {
494 		err_msg = "error sending stop condition";
495 		goto err2;
496 	}
497 
498 	for (i = 0; i < i2c_opt.count; i++) {
499 		error = read(fd, &i2c_buf[i], 1);
500 		if (error == -1) {
501 			err_msg = "ioctl: error while reading";
502 			goto err1;
503 		}
504 	}
505 
506 	close(fd);
507 	return (0);
508 
509 err1:
510 	cmd.slave = i2c_opt.addr;
511 	error = ioctl(fd, I2CSTOP, &cmd);
512 	if (error == -1)
513 		fprintf(stderr, "error sending stop condition\n");
514 err2:
515 	if (err_msg)
516 		fprintf(stderr, "%s\n", err_msg);
517 
518 	close(fd);
519 	return (1);
520 }
521 
522 int
523 main(int argc, char** argv)
524 {
525 	struct iiccmd cmd;
526 	struct options i2c_opt;
527 	char *dev, *skip_addr, *i2c_buf;
528 	int error, chunk_size, i, j, ch;
529 
530 	errno = 0;
531 	error = 0;
532 
533 	/* Line-break the output every chunk_size bytes */
534 	chunk_size = 16;
535 
536 	dev = I2C_DEV;
537 
538 	/* Default values */
539 	i2c_opt.addr_set = 0;
540 	i2c_opt.off = 0;
541 	i2c_opt.verbose = 0;
542 	i2c_opt.dir = 'r';	/* direction = read */
543 	i2c_opt.width = 8;
544 	i2c_opt.count = 1;
545 	i2c_opt.binary = 0;	/* ASCII text output */
546 	i2c_opt.scan = 0;	/* no bus scan */
547 	i2c_opt.skip = 0;	/* scan all addresses */
548 	i2c_opt.reset = 0;	/* no bus reset */
549 	i2c_opt.mode = I2C_MODE_NOTSET;
550 
551 	while ((ch = getopt(argc, argv, "a:f:d:o:w:c:m:n:sbvrh")) != -1) {
552 		switch(ch) {
553 		case 'a':
554 			i2c_opt.addr = (strtoul(optarg, 0, 16) << 1);
555 			if (i2c_opt.addr == 0 && errno == EINVAL)
556 				i2c_opt.addr_set = 0;
557 			else
558 				i2c_opt.addr_set = 1;
559 			break;
560 		case 'f':
561 			dev = optarg;
562 			break;
563 		case 'd':
564 			i2c_opt.dir = optarg[0];
565 			break;
566 		case 'o':
567 			i2c_opt.off = strtoul(optarg, 0, 16);
568 			if (i2c_opt.off == 0 && errno == EINVAL)
569 				error = 1;
570 			break;
571 		case 'w':
572 			i2c_opt.width = atoi(optarg);
573 			break;
574 		case 'c':
575 			i2c_opt.count = atoi(optarg);
576 			break;
577 		case 'm':
578 			if (!strcmp(optarg, "no"))
579 				i2c_opt.mode = I2C_MODE_NONE;
580 			else if (!strcmp(optarg, "ss"))
581 				i2c_opt.mode = I2C_MODE_STOP_START;
582 			else if (!strcmp(optarg, "rs"))
583 				i2c_opt.mode = I2C_MODE_REPEATED_START;
584 			else
585 				usage();
586 			break;
587 		case 'n':
588 			i2c_opt.skip = 1;
589 			skip_addr = optarg;
590 			break;
591 		case 's':
592 			i2c_opt.scan = 1;
593 			break;
594 		case 'b':
595 			i2c_opt.binary = 1;
596 			break;
597 		case 'v':
598 			i2c_opt.verbose = 1;
599 			break;
600 		case 'r':
601 			i2c_opt.reset = 1;
602 			break;
603 		case 'h':
604 		default:
605 			usage();
606 		}
607 	}
608 	argc -= optind;
609 	argv += optind;
610 
611 	/* Set default mode if option -m is not specified */
612 	if (i2c_opt.mode == I2C_MODE_NOTSET) {
613 		if (i2c_opt.dir == 'r')
614 			i2c_opt.mode = I2C_MODE_STOP_START;
615 		else if (i2c_opt.dir == 'w')
616 			i2c_opt.mode = I2C_MODE_NONE;
617 	}
618 
619 	/* Basic sanity check of command line arguments */
620 	if (i2c_opt.scan) {
621 		if (i2c_opt.addr_set)
622 			usage();
623 	} else if (i2c_opt.reset) {
624 		if (i2c_opt.addr_set)
625 			usage();
626 	} else if (error) {
627 		usage();
628 	} else if ((i2c_opt.dir == 'r' || i2c_opt.dir == 'w')) {
629 		if ((i2c_opt.addr_set == 0) ||
630 		    !(i2c_opt.width == 0 || i2c_opt.width == 8 ||
631 		    i2c_opt.width == 16))
632 		usage();
633 	}
634 
635 	if (i2c_opt.verbose)
636 		fprintf(stderr, "dev: %s, addr: 0x%x, r/w: %c, "
637 		    "offset: 0x%02x, width: %u, count: %u\n", dev,
638 		    i2c_opt.addr >> 1, i2c_opt.dir, i2c_opt.off,
639 		    i2c_opt.width, i2c_opt.count);
640 
641 	if (i2c_opt.scan)
642 		exit(scan_bus(cmd, dev, i2c_opt.skip, skip_addr));
643 
644 	if (i2c_opt.reset)
645 		exit(reset_bus(cmd, dev));
646 
647 	i2c_buf = malloc(i2c_opt.count);
648 	if (i2c_buf == NULL)
649 		err(1, "data malloc");
650 
651 	if (i2c_opt.dir == 'w') {
652 		error = i2c_write(dev, i2c_opt, i2c_buf);
653 		if (error) {
654 			free(i2c_buf);
655 			return (1);
656 		}
657 	}
658 	if (i2c_opt.dir == 'r') {
659 		error = i2c_read(dev, i2c_opt, i2c_buf);
660 		if (error) {
661 			free(i2c_buf);
662 			return (1);
663 		}
664 	}
665 
666 	if (i2c_opt.verbose)
667 		fprintf(stderr, "\nData %s (hex):\n", i2c_opt.dir == 'r' ?
668 		    "read" : "written");
669 
670 	i = 0;
671 	j = 0;
672 	while (i < i2c_opt.count) {
673 		if (i2c_opt.verbose || (i2c_opt.dir == 'r' &&
674 		    !i2c_opt.binary))
675 			fprintf (stderr, "%02hhx ", i2c_buf[i++]);
676 
677 		if (i2c_opt.dir == 'r' && i2c_opt.binary) {
678 			fprintf(stdout, "%c", i2c_buf[j++]);
679 			if(!i2c_opt.verbose)
680 				i++;
681 		}
682 		if (!i2c_opt.verbose && (i2c_opt.dir == 'w'))
683 			break;
684 		if ((i % chunk_size) == 0)
685 			fprintf(stderr, "\n");
686 	}
687 	if ((i % chunk_size) != 0)
688 		fprintf(stderr, "\n");
689 
690 	free(i2c_buf);
691 	return (0);
692 }
693